426 



NA TURE 



[August 31, 1905 



due to some genetic relation between the two 

 organisms, the one producing the other at various 

 times and in divers places in the same way as the 

 normal Linaria vulgaris from time to time and in 

 this spot and the other produces the peloric form? 

 Have we caught one species in the act of producing 

 another? E. F. 



EXPERIMENTAL MORPHOLOGY. 

 Einleitiiiig in der experimentelle Morphologic der 

 Tiere. By Dr. Hans Przibram. Pp. 142. (Leipzig 

 and Vienna : Franz Deulicke, 1904.) Price 4 marks. 



THIS volume is divided into thirteen practically 

 independent sections, and represents the " fast 

 unveranderte Drucklegung " of a course of lectures 

 delivered by the author during the session of 1903-4 

 at the Wiener University. The author has been in- 

 duced to publish these lectures by the belief that all 

 previous works of a general nature dealing with 

 experimental embryology have either been written 

 wholly in support of particular theories (e.g. Driesch, 

 Haacke, Herbst) or only deal with a portion of the 

 subject [e.g. Davenport, Hertwig, Korschelt, Maas, 

 Morgan, Wilson, Ziegler). The present work is 

 intended, therefore, as an introduction to the whole 

 subject from an impartial standpoint. 



In the first section, which deals mainly with the 

 scope of experimental morphology, the author, after 

 weighing the various names which have been 

 proposed for the science — Entwicklungsmechanik, 

 Entwicklungsphysiologie, kausala Morphologic, &c. 

 — adopts Davenport's name, " experimental morph- 

 ology," but defines it as including not only the ex- 

 perimental study of the factors determining form in 

 ontogeny, but also in phylogeny (Umvandlungs- 

 physiologie), so that Driesch 's term " rationelle 

 Morphologie " would seem to be more appropriate. 



The uncertainty as to the proper scope of the science 

 which this considerable choice of names exhibits is in 

 part due to its recent growth, but it is also due in no 

 small measure to the close connection in which 

 experimental morphology must always stand to the 

 other sciences. 



That the author has not been more successful than 

 his predecessors in determining suitable limits to the 

 subject is very clearly shown by his treatment of the 

 section dealing with the " Specifische Bestimmung. " 

 In this section the author describes the influence of 

 relationship in transplantation experiments, and the 

 persistence of specific characters in the transplanted 

 tissues. He then refers to Heape's experiment, in 

 which normal development of an Angora rabbit is 

 obtained, though transplanted shortly after fertilisa- 

 tion into the uterus of a Belgian rabbit, from which, 

 however, the author's conclusion that transfusion of 

 strange blood has no morphogenic influence hardly 

 follows. Following this is an account of immunity 

 and blood relationship experiments. If it is difficult 

 to see why these subjects should be included in a 

 science ostensibly dealing with the factors determin- 

 ing form, this difficulty is still greater when the 

 author proceeds to consider the distribution in the 

 NO. 1870, VOL. 72] 



animal kingdom of the various proteid substances 

 contained in muscle fibre. 



In the fourth section, " Die Bewegung-Taxis," 

 the author gives a series of very far-fetched com- 

 parisons between the behaviour of unicellular animals 

 and of the higher Metazoa. The sensation of thirst is 

 compared with the hydrotaxis of the Mycetozoa, and 

 Davenport's example is followed in regarding as 

 rheotaxis the behaviour of fish in swimming against 

 the stream, the only position in which they are able 

 to breathe. Finally, the " Thigmotaxis " exhibited by 

 an oxytrocha moving round a spherical egg, unable 

 to leave its surface, is compared with the retreat of a 

 cat into the corner as a dog approaches, or to the 

 preference shown by many people for those seats in a 

 restaurant which have their backs to the wall ! 



In the twelfth section, " Die Vererbung," the 

 author, after giving a brief account of the current 

 theories of heredity, shows how these are in 

 " schonster Uebereinstimmung " with our recent 

 knowledge concerning the constitution of the nucleus. 

 This agreement is obtained by assuming reduction 

 to consist in the elimination of whole chromosomes 

 during the maturation divisions, the view that this 

 process represents the belated union of the paternal 

 and maternal chromosomes not being mentioned. 



In the final section, " Die Artwandlung," the 

 author discusses the influence of external factors in 

 causing transmissible variations. 



The wide range covered by the book, the thirteen 

 sections of which only average ten pages each, has 

 resulted in a somewhat superficial mode of treat- 

 ment, and neither in point of comprehensiveness nor 

 of impartial treatment can the book be said to fill 

 the want which, according to the author, has been left 

 unsatisfied by all previous workers. G. C. C. 



ATLAS OF EMISSION SPECTRA. 

 Atlas of Emission Spectra of most of the Elements. 

 By Drs. Hagenback and Konen. English trans- 

 lation by Dr. A. S. King. Pp. v + 70 and plates. 

 (Jena : G. Fischer ; London : Wm. Wesley and 

 Sons, 1905.) Price 27s. 



THIS atlas comprises the results of an investi- 

 gation of the spark, arc, and flame spectra of 

 most of the chemical elements. Twenty-eight charts 

 are given showing heliographic reproductions of 

 photographs taken with the aid of two small Rowland 

 concave gratings, each of i metre radius and 20,000 

 lines to the inch. One of the gratings had a ruled 

 space 9 cm. broad, and was used chiefly for the region 

 of shorter wave-length. The other had a breadth of 

 5 cm., and was used to photograph the less re- 

 frangible portion of the spectrum. For each group 

 of metals two charts are given, one showing the 

 normally visual part of the spectrum, the other the 

 violet and ultra-violet region. The dispersion given 

 by the gratings is such that the length of spectrum 

 from the K line of calcium (A 3934) to the D lines of 

 sodium (X 5893) is about 4.5 inches, or 11 cm., each 

 scale division on the reproductions corresponding to 



